Missouri flooding has left one four year old boy dead and his mother missing, after flash flooding his central Missouri, according to reports.

Sergeant Dan Crain, a spokesman for the Missouri State Highway Patrol in Rolla, has said, "It appears they were washed out of their vehicle when it was swept from a small tributary into a larger creek."

The spokesman added that the vehicle had now been found, but he did not release any details about the identities of the young boy and the woman.

Authorities have confirmed that the vehicle the woman and child were in was swept off a road they were traveling on earlier this week.

The region suffered from heavy rains on Monday through Wednesday, causing major flooding around the Waynesville area, which is about 130 miles southwest of St Louis.

The flooding forced authorities to order an evacuation for many homes and buildings in the area, and on Tuesday Missouri Governor Jay Nixon declared a state of emergency.

Nixon also oversaw the commissioning of 50 military police from the Missouri National Guard to help protect property in flooded areas to ensure looting and burglaries did not take place.

The Gasconade River also flooded, and numerous parts of Interstate 44 had to be closed down to traffic.